Measurement of Z +? Production and Search for Anomalous Triple Gauge Couplings in Proton-antiproton Collisions at ?S = 1.96 Tev

by Deng, Jianrong

Abstract (Summary)

We present a measurement of ppbar->Z? + X -> e+e-? + X production using proton-antiproton collision data collected at the Collider Detector at Fermilab at a center of mass energy of 1.96 TeV. Z? production provides a direct test of the triple neutral gauge couplings. A measurement of Z? production cross section and search for anomalous ZZ? and Z?? couplings are presented.

The data presented are from 1.1 fb-1 of ppbar integrated luminosity collected at the CDF Detector. Electrons from Z decays are selected with Et > 20 GeV. Photons (Et > 7 GeV) are required to be well-separated from the electrons. There are 390 ee? candidate events found with 1.1 fb-1 of data, compared to the SM prediction of 375.3 Ã Â± 25.2 events. The Standard Model prediction for the cross section for ppbar-> e+e-? + X production at ?s = 1.96 TeV is 4.5 Ã Â± 0.4 pb. The measured cross section is 4.7 Ã Â± 0.6 pb. The cross section and kinematic distributions of the ee? events are in good agreement with theoretical predictions.

Limits on the ZZ? and Z?? couplings are extracted using the photon Et distribution of ee? events with Mee? > 100 GeV/c2. These are the first limits measured using CDF Run II data. These limits provide important test of the interaction of the photon and the Z boson.